AWWA ACE58092

Over time, deposits (mineral precipitant scale, corrosion byproducts and microbiological growth) in waterlines reduce the carrying capacity of the main, reduce distribution system pressures, increase pump energy costs and may result in safety concerns for the public. There are many options for improving flows in piping that is experiencing deposition. These options can include either mechanical or chemical means. One of the chemical options that are widely used is phosphate treatment. Properly selected and dosed phosphate products can remove deposits and prevent mineral scale, corrosion byproducts and microbiological growth from reoccurring. This paper gives calculated electrical costs for different size piping and relates that to the effects of scale or mineral depositions. The effects of phosphate treatment is demonstrated by a case study of a Midwestern utility that realized a 12% reduction in electric pumping costs and improved hydrant flows averaging 65%. Includes 5 references, tables, figures.